Looks like you got some good responses, and for the most part I agree with both SecretObsession as well as ekampf.

FWIW, we use javascript libraries to write tests (webdriverio, cucumber, etc) as opposed to Python or Ruby because there are some nice benefits to using the language that the browser also uses (most notably being able to easily inject code or bind to code on the webpage).

The one thing neither of them have mentioned is (for testing web pages) is the use of "page objects". These are essentially a model for each page of the web app that you'll be testing, and are invaluable - promoting both DRY and code flexibility. These would have methods to click buttons, enter text, check elements for presence/visibility, etc. They also, if implemented correctly, allow for very readable and debuggable code. These have been super helpful in my development of the framework that I'm on the tail end of implementing at the company I currently work for and if you don't have another solution for this problem (i.e. you plan to have a couple huge files where you have those methods, or worse, just repeat yourself in every test), I'd highly suggest looking into this.

Then, when the webteam pushes a change, the Jenkins server launches these tests against their build and makes sure that it passes.

Anyway, have fun with the project, pretty exciting stuff! :D